Vat dye composition



Patented Dec. 23, 1941 UNITED STATE S PATENT OFFICE vA'r DYE COMPOSITIONJean G. Kern, Buffalo, N. Y., assignor to National Aniline & ChemicalCompany, Inc., New York, N. Y., a corporation of New York No Drawing.Application January 28, 1939,

Serial No. 253,345

further treatment to fix the dye. In general, vat

15 Claims.

In the art of dyeing with vat dyes, two general methods are ordinarilyemployed. In accordance with one method, a vat comprising an alkalinesolution of a reduced vat dye is prepared and the fibrous material to bedyed is worked in this solution whereby the fiber takes up the reducedcompound of the dye. The material is then subjected to oxidation andother finishing treatments to convert the vat dye from the reduced tothe unreduced form and further complete the fixing of the dye andfinishing of the material. In accordance with the other method the dyeis applied to the material to be dyed while in the unreduced form; it isthen subjected to a reducing treatment whereby the dye is converted tothe soluble form in the presence of the fiber and is then taken up bythe fiber. It is then subjected to oxidation and/or other finishingtreatments tofix the dye on the fiber, remove undesired residualmaterial, and complete th'e finishing of the material.

In dyeing with vat dyes by the latter method, one of two procedures isusually followed, depending upon whether the material is to be dyed asolid color or with a pattern in one or more colors. If the material isto be dyed a solid color, the pigment padding (pad and jig) process isordinarily employed, and if the material is to be dyed with a pattern,the printing process is generally utilized,

dye printing pastes, in addition to the unreduced vat dye, containsubstances which in themselves do not reduce the vat dye under theconditions of the printing operation but which in subsequent operationsreact with the dye to convert it to the soluble form (such as sodiumformaldehydesulfoxylate and potassium carbonate), other substances orassistants which pro mote the reduction of the dye and/or absorption ofthe reduced compound by the fiber, and suitable gums or thickeners. Thefixing treatment usually comprises subjecting the printed fabric to aso-called steaming or ageing" In the pigment padding process, theunreduced vat dye in finely-divided form is suspended in a suitablesuspension medium, usually water containing added materials such asthickeners and alkaline substances. The material to be dyed is passedth'rough this suspension, the fiber mechanically picks up the particlesof insoluble dye, and the material is subsequently worked in a reducingbath whereby the dye is reduced to the soluble form and is absorbedand/or adsorbed by the fiber. The material is finally subjected tooxidation and finishing treatments to reconvert the dye to the insolubleform, fix it on the fiber, and further complete the finishing of thematerial.

The printing process of dyeing a textile fabric generally involvesapplying a so-called printing paste to the fabric in the form of adesign (e. g., by meansof a screen, a stencil, or an engraved roll), andthen subjecting the printed fabric to the pigment padding or printingprocesses, the

success of the operation is in a large measure dependent upon theuniformity with which the vat dye (e. g., the unreduced vat dye) isapplied to the fabric. The vat dyes in unreduced form, as is well known,are insoluble in water and are not readily wetted by water. In preparinga padding bath or printing paste it is important that the vat dye be infinely-divided form, that it be uniformly distributed throughout thebath or paste, and in condition such that it may be taken up by thefiber. Further, it is important that the vat dye be capable of rapid andsubstantially complete reduction to the reduced form. The vat dyes,especially those which are intended for use in the pigment padding andprinting processes, are generally marketed in the form of so-called dyepastes or color pastes, and dye powders. A dye paste of this kind isusually an aqueous mixture or suspension of finely-divided vat dye,which generally makes up 10 to 20 per cent of the paste. The pasteusually contains a small amount of a dispersing agent such as Leukanol(a condensation product of femaldehyde and a naphthalene sulfonic acid)and the remainder is mainly water, a part of which is sometimes replacedby other liquids such as amino alcohols, polyhydroxy alkyl ethers orother polyhydroxy alkyl compounds, and cyclic ethers; as, for example,glycol ethers, glycol, glycerine, poly-glycerines, poly-glycols', .etc.These vat dye pastes are ordinarily produced by stirring the dispersingand other agents with the filter cake of the dye resulting fromfiltration of a precipitate of the dye obtained in its manufacture, orby precipitation in the finelydiivided form from a vat or sulfuric acidor other solution.

As noted above. vat dyes for use in the preparation of padding baths andprinting paste may be supplied in the form of vat dye powders. In thecase of the powders, it is important that the vat dyes contained thereinnot only have the properties pointed out above in connection with thevat dye pastes, but also that the powders be rapidly converted touniform suspensions of the vat dye. Especially successful vat dyepowders are described in my United States Patents Nos. 2,067,926 and2,145,193. These vat dye powders are prepared by incorporating with theusual vat dye paste, e. g., one containing a small amount of adispersing agent) a soluble salt of an acid alkyl ester of anoxygen-containing polybasic inorganic acid (e. g., a soluble salt of thesulfuric acid ester of a lower aliphatic alcohol) and preferably also anadded substance such as, for example, dextrine, sugar, gum arabic, andthe like, and then drying and grinding the resulting composition.

It is the principal object of the present invention to provide vat dyecompositions which are productive of excellent dyeings and printingswhen employed in the usual ways. Another object of the invention is toprovide vat dye pastes and powders which are adapted for use in the eiilcient preparation of padding baths and printing pastes containinguniformly distributed therethrough the finely-divided particles of thevat dves. Another object of the invention is to provide vat dye pastesand powders which when used in the preparation of padding baths andprinting pastes are productive of compositions characterized by themarked efficiency with which the dye is initially taken up by the fiberand the increased brilliancy andstrength of the resulting dyeings andprintings as compared with the dveings and printings obtained by the useof padd ng baths and printing pastes prepared from ordinarv vat dyepastes. A further object of the invention is to provide vat dye pasteswhich remain fluid on standing and which may be easily and quickly mixedwith the ingredients making up the conventional padding baths andprinting pastes to form homogeneous compositions containing the vat dyesin well-dispersed condition.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The vat dye compositions of the present invention consist essentially ofa vat dye compound in the unreduced or other form and a soluble organicester of a saturated aliphatic mono-carboxylic acid containing not morethan 8 aliphatic carbon atoms joined carbon to carbon. The esters thathave been found to be adapted for use in the compositions of theinvention contain at least one sulfate, sulfonate, or phosphate group,and their ester groups are free from aliphatic radicals containing morethan a total of 12 aliphatic carbon atoms per aliphatic radical and fromstraight carbon chains of more than 8 aliphatic carbon atoms. Inspeaking of soluble esters it is meant esters that are soluble in waterand or in alkaline solutions. The invention is based upon the discoverythat esters of this class possess a combi nation of properties whichmake them valuable for use in compositions containing vat dyes, and

especially in vat dye compositions in paste or powder form intended foruse in the preparation of padding baths or printing pastes.

In preparing a vat dye paste in accordance with the present invention, avat dye, usually in the form of a press cake (a mixture of a vat dye infinely-divided form with water as obtained in the course of manufactureof the dye) is mixed with an ester of the above class and alsopreferably with a dispersing agent (for example, Leukanol or sulfitewaste liquor).

The resulting mixture isthen diluted with water to the desireddye-strength; or if the paste is to be a so-called non-drying paste,that is to say, one in which the water is replaced in whole or part by awater-miscible, high-boiling alcohol such as isobutyl alcohol,glycerine, glycol, polyglycerines, polyglycols, and alkyl ethers ofthese compounds, the requisite amount of such alcohol is added to themixture and water is removed therefrom by evaporation until the pastehas the desired dye strength. The compositions prepared in this waycomprise fluid pastes consisting of dispersions of the finely-dividedvat dye. The compositions are relatively stable and do not settle onstanding over a relatively long period of time. Furthermore, as comparedwith many available vat dye pastes, they are in a fluid or free-runningstate. Thus they are adapted to be efliciently and quickly incorporatedwith the other ingredients of padding baths and printing pastes toprepare such baths and pastes in a form such that the resultingcompositions may be emciently employed in dyeing and printing.

When preparing the vat dye compositions of the present invention in theform of vat dye flakes, scales, grains, powders, and the like, thepastes prepared as described above, but usually with little or nohigh-boiling water-miscible alcohol therein, may be concentrated and ordried, as by means of a vacuum or atmospheric rotary drum drier, byspray drying, or by means of the addition to the paste of an anhydroushydrate-forming inorganic salt. It is preferable, however, whenpreparing the powders to add to the paste before drying a substance suchas sugar, dextrine, gum or starch, or derivatives of alginic acidsand/or other suitable additions. In preparing the dry products employinga mechanical drier, the dry product scraped from the drier is in theform of flakes,'scales or grains, and may be used as such, but may alsobe ground to produce a finely-divided powder.

The esters employed in the vat dye compositions of the present inventionare such as are derivable from any saturated aliphatic monocarboxylicacid containing less than 9 carbon atoms (such as, for example, aceticacid, propionic acid, normal and isobutyric acids, normal and isocaproicacids, normal and isovaleric acids, normal and isoheptylic acids,caprylic acid, their isomeric acids, etc.), and an organic hydroxycompound, especially an alcohol, containing not more than Baliphaticcarbon atoms in a straight carbon chain and a total of not more than 12aliphatic carbon atoms. The aliphatic monocarboxylic acids from whichthe esters are derivable may contain substituents; such as, for example,halogens, hydroxy], amino, and aromatic radicals.

The said esters may be derivatives of openchain aliphatic monohydric orpolyhydric alcohols, or of monoor polyhydric hydroaromatic alcohols,cycloaliphatic alcohols, heterocyclic alcohols, aralkyl alcohols, mixedaliphatichydroaromatic alcohols, or of monoand polyhydric alcoholethers. As examples of such alcohols there may be mentioned ethyl,propyl, allyl, butyl, amyl, hexyl, heptyl, octyl, and the like alcohols;cyclohexanol, methyl cyclohexanol, cyclopentanol, tetrahydrofurfurylalcohol, benzyl 2,261,609 alcohol, phenyl ethyl alcohol, phenyl,methylcarbinol, the various terpene alcohols; ethylene, propylene,di-ethylene, and triethylene glycols, and the like; and the methyl andethyl ethers of ethylene, di-ethylene, or other glycols. As typicalalcohols there may .be also mentioned the following alcohols which areobtainable as by-products in the production of methanol by the catalytichydrogenation of mixtures of carbon monoxide and carbon dioxide:a-methyll-pentanol; '2-methyl-1-pentanol; 2,4-dimethyll-pentanol;3-methyl-2-pentanol; 2,4-dimethylare particularly valuable for use inthe vat dye compositions.

Where the appended claims an ester of an alcohol and an aliphaticmonocarboxylic acid is referred to it will be understood that an esterderivable from an alcohol selected from any of the above describedclasses and an aliphatic monocarboxylic acid is intended, unlessotherwise indicated.

It will be understood that the alcohols from which the esters arederivable may contain substituents which do not alter the essentialphysical or chemical characteristics of the esters. As indicated above,polyhydric alcohols may be employed and in this case either one or bothof the hydroxyl groups may be esteriiied with the carboxylic acid groupof the acid employed. When only one of the hydroxyl groups isesterifled, one or more free hydroxyl groups remain, which are notobjectionable and in some cases appear to have an advantageous effectupon the properties of the esters. The amino group may also be mentionedas an example of a substituent which may be present in the alcoholresidue of the esters, valuable esters adapted for use in the vat dyecompositions being derivable from amino alcohols.

It has been found that the best results are obtained with esters of theabove class which contain sulfonate and/or sulfate groups and whichdisplay high solubility in aqueous solutions and/or alkaline printingpastes. ingly, the preferred esters are those which are derived fromlower aliphatic alcohols (l. e., containing 2 to 6 carbon atoms),cycloalkyl alcohols, and aromatic alcohols. It has been found thatesters which are derivatives of isobutyl alcohol are of markedly highvalue. For similar reasons, the esters derived from the shorterchainlength aliphatic monocarboxylic acids (i. e., containing 2 to 4carbon atoms) are of particular value. Acetic acid is preferred as thealiphatic monocarboxylic acid. While preferred esters contain one ormore sulfonate and/or sulfate groups, it has been found that thoseesters which contain at least one sulfonate group ar especiallyvaluable. Further, although the solubilizing group of the sulfonatedand/or sulfated esters may be in the ester radical, the acyl radical, orboth, it is preferred to employ such esters in which the solubilizinggroup, preferably a Accordethane sulionate group, is in the acyl radicaland the ester radical is free from solubilizing groups.

- view of the foregoing disclosure, it will be rea ly apparent that alarge number of esters are available for use in the compositions of theinvention. The following esters (described in the form of the free acidsof the inorganic acidresidues contained therein) are given as examplesof typical esters of the class hereinabove disclosed: isobutylsulfoacetate; n-amyl-betasulfo-beta-furylpropionate; n-amylsulfoacetate; isobutyl sulfatobutyrate; isobutyl phosphatobutyrate;C-phenyl-isobutyl sulfopropionate; normal-hexyl sulfoacetate;cyclohexyl-sulfoacetate; normal-amyl sulfatobutyrate; 4-methyl1- pentylsulfoacetate; isobutyl sulfobutyrate; 2- methyl-l-pentyl sulfobutyrate;2,4-dimethyl-1- pentyl sulfoacetate; tri-isopropylcarbinol sulfoacetate;glyceryl-di-(sulfoacetate) 4-methyl-1- hexyl sulfoacetate;monoethyl-ether of triethylene glycol sulfoacetate; triethylene glycolsulfoacetate; triethylene glycol sulfatoacetate; mono-acetylglycerinesulfoacetate; methyl-cyclohexyl sulfoacetate; tetrahydroiurfurylsulfobutyrate; tetra-hydrofuriuryl-aminoethyl sulfoacetate;phenyl-methyl-carbinol sulfoacetate; secondary octyl sulfoacetate; octylsulfoacetate; thesulfuric acid esters or phosphoric acid esters of theglyceryl esters of acetic acid; the glyceryl esters of glycollic orlactic acid which are "sulfated or phosphated in the glyceryl radicals;

the sulfoethyl ester of beta-hydroxyethylamidopropionic acid (thesulfoethyl ester of N-hydroxyethyl succinamic acid);sulfatopropyleneglycol acetate; sulfatoethyleneglycol butyrate; and themonosulfate of glycerine monosulfoacetate.

The esters employed in the present invention may be prepared in anywell-known or suitable manner. For example, the sulfated esters may beprepared by reacting the ester of the corresponding unsaturatedaliphatic acid with concentrated sulfuric acid or the ester of thecorresponding hydroxy-aliphatic acid with chlorsulfonic acid, andneutralizing the resulting product with the desired inorganic or organicbase. The sulfonated esters may be prepared by reacting the ester of thecorresponding halogenated aliphatic acid with sodium sulfite.

The esters are preferably employed in the form of their neutral solublesalts. The alkali-metal salts, and the salts obtained by neutralizingthe acid esters with organic derivatives of ammonia, are especiallyimportant. As examples of suitable organic derivatives of ammonia, the

following are mentioned: the alkylolamines (e. g., mono-, di-, ortriethanolamine); the alkylol diamines (e. g., l,2-di-(2'-ethanolamino)and l,3-di-(2'-ethanolamin0) -2-propanol); the quaternary alkylolamines,the diquaternary alkylolamines (e. g., tetra-hydroxyethylamine ammoniumhydroxide, hexa-hydroxy-ethyl-ethylene diammonium hydroxide); and thequaternary aralkyl-alkyl ammonium hydrcxides or thearalkyl-hydroxyalkyl-ammonium hydroxides (e. g., tri-methyl-benzylammonium hydroxide, tri (hydroxy ethyl) benzylammonium hyroxide, etc.).

The valuable eflects resulting from the inclusion of the above describedesters in vat dye compositions in accordance with the present inventionare noticed both in vat dye pastes and in powders from which dyeingcompositions (baths and printing pastes) are prepared and also in the ,parently to prevent flocculation of the dye particles. In the vat dyepowders, the esters make possible the rapid disintegration of the dyeparticles in dye baths and aqueous printing compositions, a result whichis believed to be due to the fact that the esters are so combined orcommingled with the vat dye particles as to :form therewith acomposition resembling a solid dispersed suspension. The particles ofthe vat dyes, therefore, are prevented from combining to form largerparticles which would be difficult to disperse in a padding bath orprinting paste.

When the vat dye pastes and powders are incorporated with the otherusual ingredients of vats, padding baths, or printing pastes, severaladvantageous results are obtained. First, as previously noted, thecompositions may be mixed readily with such ingredients to formhomogeneous dyeing compositions. Further, it appears that the esters actto increase the solubility of ieuco dyes and increase the strength andbrilliancy of the dyeings and printings obtained. This is because, whileieuco vat dyes are regarded as being soluble in alkaline solutions, andbecause of this solubility may be taken up by the fiber to be dyed, theyare not freely soluble and their increased solubility caused by theesters accelerates the rate of their absorption oradsorption by thefiber.

The vat dye compositions of the present invention are particularlyvaluable as compared with ordinary vat dye compositions when they areapplied to synthetic fibers composed of regenerated cellulose, or tounbleached natural fibers, such as cotton and raw silk. It is known thatthese latter fibers do not, as a rule, readily absorb the reduced vatdyes because of their coating of natural waxes which act as resistagents.

As before stated, the soluble esters of this invention may be used perse or in admixture with other substances ordinarily used in the art ofdyeing or printing textiles. These substances may be in the nature ofthe alkyl partial inorganic esters specifically disclosed in my patentsabove referred to, other substances used in dyeing and printing, such asthe alkylolamines, polyhydric alcohols, and ethers, e. g., the ethers ofdiethylene glycol, glucosic compounds, dextrines, gums, starches, etc.,or compounds in the nature of printing catalysts, such as heavy metalcompounds or the heavy metal salts of alkyl partial esters, such asisobutyl-nickel-sulfate, or the heavy metal salts of the solublecarboxylic esters of the present invention, themselves.

Inasmuch as the quality and dispersibility of the resulting dyecomposition are dependent to a considerable extent upon the originaldegree of dispersion of the dye in the suspension or in the dry form,the vat dye is preferably treated in the highly dispersed form. Asuitable dispersing agent is preferably incorporated into the dispersionor suspension so as to aid in preventing precipitation and agglutinationof the dye particles during storage or during the drying and to increasethe fluidity and render easier the incorporation of the soluble salts ofthe carboxylic acid esters.

Among the dispersing agents which may be employed for this purpose theremay be mentioned, for example, the sulfonic acids of henzene,hydyroxybenzenes, naphthalene, hydroxynaphthalenes, their nuclear alkyl,nuclear aralkyl, and hydrogenated derivatives, as well as aldehydecondensation products thereof (as for example,2,6-naphthalene-disulfonic acid, 1.7- naphthalene-disulfonic acid,2,8-naphthalenedisulfonic acid, isopropyl-naphthalene-sulfonic acids,dibutyl-naphthalene-sulfonic acids, amylnaphthalene-sulfonic acids,butyl-benzyl-naphthalene-sulfonic acids, cyclo-hexyl-naphthalenesulfonicacids, methylene-(ii(p-naphthalene-sulfonic acid),methylene-di(di-isopropyl-naphthalene-sulfonic acid), in the form of thefree acids or salts (e. g., alkali metal salts), etc.; sulflte cellulosewaste liquors and their mildly oxidized products and evaporatedresidues; sulfonated resins; abietene, abietine, and abietane sulfonicacids; soaps; sulfonated higher fatty acids, fats and oils; and thelike, as well as mixtures of two or more of such substances.

Further, additional substances having diluent antifoaming, assisting,wetting, catalytic, enolyzing, or other suitable action in thesubsequent use of the compositions may also be incorporated into thecompositions of the present invention, preferably while the latter are,in the form of aqueous suspensions or in the form of non-drying pastescontaining high boiling alcohols or alcohol ethers.

In preparing the vat dye pastes and powders in accordance with apreferred manner of proceeding, the mixture of vat dye in aqueous orhigh boiling solvent dispersion is agitated with the appropriate amountof the carboxylic acid ester salt together with the other substances, ifadded, until a homogeneous paste is formed, or the mixture of theaqueous suspension of the dispersed vat dye and acarboxylic acid estersalt together with the other substances, if added, is evaporated withagitation until a thick paste is formed, with or without the aid ofvacuum and preferably at a temperature not exceeding C. The resultingpaste constitutes a valuable vat dye paste. If desired, it may bebrought to substantial dryness to form a dry vat dye composition. Thus,the paste may be evaporated to dryness on an atmospheric or vacuumrotary drum drier, and the dry product scraped off in the form offlakes. scales, or grains which may be used as such; or the paste, withor without preliminary evaporation, may be admixed with a suitablehydrateforming soluble salt in an anhydrous condition,

such as anhydrous trisodium phosphate, and the,

admixture stirred to produce a dry product. If desired, the dry productmay be disintegrated in any suitable manner into a powder.

Mixtures of the carboxylic acid ester salts or mixtures of them withalkyl inorganic ester salts, disclosed in my patents referred to abovemay also be employed in accordance with the present invention. Further,the esters used in the compositions of the invention may be usedtogether with or in place of the esters disclosed in my applicationsSerial Nos. 253,346 and 253,347, filed of even date herewith.

The amount of the soluble carboxylic acid esters employed in thepreparation of the compositions of the present invention may be variedover a considerable range, depending in part' upon the concentrationof-vat dye in the composition, the use to which the composition is to beput, and whether or not other diluents and other materials having acatalytic, assisting, wetting, enolyzing, dispersing, or other action,are included in the composition.

The invention may be employed in connection with vat dyes of all typesincluding those derived from anthraquinones, indophenols, variousindigoid, thioindigoid and indirubin compounds, etc.: as for example,indanthrones, pyranthrones, flavanthrones, dibenzanthrones,isodibenzanthrones, perylene quinones, anthranthrones, dibenzpyrenequinones, anthrimidocarbazoles, naphthacrldones, indigo, thioindigo,indirubin, etc., including derivatives thereof, such as theirhalogen,'nitro, sulfur, and/or alkoxy derivatives.

It should be noted that while the vat dyes in the compositions of theinvention are preferably in the unreduced form, they may also be in thereduced or leuco form. For example, leuco ester salts of vat dyes andleuco compounds of vat dyes prepared by careful acidification of analkaline vat, or by other methods, may be used, if desired.

Although it is generally preferable and desirable, in order to take fulladvantage of their properties, to employ the esters in vat dye pastes inthis way, the dye may be introduced into the mixture in the form of apress cake or an ordinary dye or other form of paste, the ester oresters being added at any desired or suitable point in the preparationof the compositions.

In the forgoing description, the use of the vat dye compositionsin thedyeing and/or printing of textile materials has been stressed since thisis the most important application of the compositions. The compositions,however, especially when in the form of powders, may be used in thepreparation of dispersions of vat dyes for use in the pigment form inthe dyeing of paper, the tinting of fibers and other materials, and thelike. The ready dispersibility of the compositions makes them especiallyvaluable for such purposes.

The invention will be further described in connection with the followingspecific examples (in which the parts are by weight) which are givencondition on standing. The paste is especially adapted for incorporationwith the usual additional ingredients for the preparation of paddingbaths and printing pastes which give dyeings and printings of increasedstrength and brilliancy as compared with the dyeings and printingsobtained with the same compositions but omitting the sodium isobutylsulfoacetate.

Example 2 Example 3 3600 parts of National Vat Pink FF(6,6'-dicider-4,4-dimethyl-thioindigo) in the form of a press cakecontaining about per cent of dye solids and the rest principally waterare mixed thoroughly with 480 parts of sulfite buck (a sulfite wasteliquor product) dissolved in 800 parts water. To the resulting mixture8.l5 parts of caustic soda, 3180 parts of dynamite g ycerine,

to illustrate the invention. It will be realized, 1

however, that the invention is not limited thereto but that changes maybe made in the materials treated and their proportions, manipulativesteps, and other conditions without departing from the scope of theappended patent claims.

Example 1 1800 parts of National Vat Brown G (di-naphthyl-thioindigo) inthe form of a press cake containing about 16 per cent of dye solids andthe rest principally water, are mixed with 36 parts of Tamol NNO (whichis the sodium salt of a naphthalene sulfonic acid condensed withformaldehyde), 80 parts of the ethyl ether of ethylene glycol and 100parts of glycerine, and 187 parts of sodium isobutyl sulfoacetate arethen added and the whole is mixed thoroughly. The resulting dilute pasteis then evaporated at a temperature of about 100 C. to form 1800 partsof a vat dye paste in which the vat dye particles are thoroughlydispersed and which remains in fluid and 540 parts of sodium isobutylsulfoacetate are added and the resulting mixtureis agitated to form adilute paste which is then evaporated as described in Example 1 to form6000 parts of a vat dye paste. Similarly to the paste described inExample 1, the vat dye paste of this example is especially adapted foruse in the preparation of padding baths and printing pastes which giveunusually valuable dyeings and printings.

Example 4 400 parts of indigo paste (containing 20 per cent pure indigoas shown by indigotin titration and resulting from the precipitation ofindigo from an alkaline solution of indoxyl by aeration) are stirredwith 2 parts Leukanol (a condensation product of naphthalene sodiumsulfonate with formaldehyde) until a thin fluid paste is obtained. 13parts cane sugar and 5 parts 2-methyl-1-pentanol sodium sulfobutyrateare then added, the mixture being stirred until solution of the sulfoalkyl ester is complete, and the resulting mixture is then evaporatedwith stirring until a thick paste is formed. The thick paste is thenevaporated to substantial dryness either by means of a rotary doubledrum drier or else placed in drying pans in vacuum. The dry product isground and screened. An indigo powder is obtained containing 80 per centindigo which. when added to water or the dye liquor, disperses readily.When employed for the preparation of an indigo vat with the aid of theusual reducing agents (e. g., sodium hydrosulfite and caustic soda) thepowder disperses instantly and reduces very rapidly producing a clearvat which dyes cotton'yarns an even blue shade of high tinctorial value.

Example 5 and screened through a 60 mesh screen. The resulting productis a violet colored powder instantly dispersible when added to water andis especially suitable for the dyeing of piece goods by the pad-jigdyeing process. When the powder is made into a printing paste containingthe usual ingredients used for the printing of vat dyes, the printsobtained therewith yield very brilliant violet shades, fully penetratedand level.

Example 6 2765 parts of Carbanthrene Flavine GC (Color Index No. 1095)press cake containing 13.8 per cent total solids, of which approximately11 per cent represent actual dyestuff, are stirred in a beaker while 95parts Tamol NNO are added until a fluid paste is obtained. Thereafter,parts trisodium citrate, 320 parts sodium isobutyl sulfoacetatedissolved in 320 parts water, and 1600 parts dynamite glycerine areadded in succession and the 5111 parts then obtained are subjected toevaporation until 3200 parts of a color paste are obtained. This pasteis then passed through a micropulverizer, finally screened through a 200mesh screen, and is ready for use as a printing color. Unusually strongand well penetrated yellow prints are obtained therewith.

Example 7 To 4410 parts Brilliant Indigo KMR (6,6'- dibrom-indigo) pastecontaining 20 per cent actual dye solids, 1800 parts dynamite glycerineare added and the mixture is then evaporated in a glycerine bath at 100C. to a total of 2923 parts of concentrated color paste. A color pasteespe-- cially suitable for printing is then obtained therefrom asfollows:

To 2260 parts .of the above concentrated color paste, 200 parts water,140 parts isobutyl sodium sulfoacetate dissolved in 172 parts water, and28 parts diacetone alcohol are added, giving a total of 2800 parts of anIndigo KMR color paste which when thoroughly mixed is screened and isthen ready for use. When made up into a vat dye printing paste, verydeep and fully penetrated navy blue shades are obtained therewith.

In the above examples, the esters used may be replaced by equivalentamounts of anyone or a mixture of the class herein disclosed; forexample, any one or a mixture of the esters specifically mentionedabove.

The process'of making the vat dye compositions of the invention, eitherin paste, powder, or flake form, is further applicable to any vat dye.Thus any vat dye of the previous examples may be replaced by any of thefollowing:

- Color Index No. Brilliant Indigo 4G 1189 National Vat Scarlet G 1228National Vat Violet R 1222 National Vat Green G 1199 Carbanthrene YellowG 1118 Carbanthrene Golden Orange 2RT 1097 Carbanthrene Golden Orange G1096 CarbanthreneBlue Green FFB 1173 Carbanthrene Violet 2R 1104Carbanthrene Dark Blu DR 1099 Carbanthrene Flavin GC 1095 CarbanthreneBlue GCD 1113 National Vat'Orange R 1217 The process is of special valuefor the compounding of blacks of the anthraquin'one orindigo-thioindigoid series.

The esters of this invention may also be added directly to printingpastes whereby unusual re- Example 8 A standard printing thickener isprepared as foll0ws:

Parts Corn starch British g 300 Gum tragacanth 5% solution" 100 Water500 are thoroughly mixed together and boiled to a smooth paste. To 520parts of the above paste are added 170 parts K200: and 60 parts H20. andheat applied until a homogeneous paste is obtained. After cooling ofthis paste to about 150 F. there are added 140 parts sodium formaldehydesulfoxylate, 50 parts glycerine and 60 parts water, and the pastestirred until all ingredients are thoroughly mixed and dissolved. A bluevat dye printing paste is then prepared by adding to 200 partsCarbanthrene Blue GCD (Color Index No. 1113) 680 parts of the aboveprinting thickener, and parts n-amyl sodium sulfoacetate, stirring untilthe ingredients are thoroughly mixed and dissolved. Cotton and rayonfabrics are printed therewith by means of a rotary intaglio printingmachine; the material is then dried and aged for 4 minutes in anair-free ager at 102 C. (saturated steam) after which the prints arerinsed in cold running water, soaped at the boil, rinsed, and dried.Thus a very brilliant heavy shade of blue is obtained which showssuperiority in brilliance, penetration, levelling and fastness tocrocking versus prints obtained with the same printing paste but whenthe n-amyl sodium sulfoacetate has been left out.

In the above example the n-amyl sodium sulfoacetate may be replaced byany one of the esters disclosed above.

I claim:

1. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding processes comprising, inaddition to a vat dye compound and a small amount of a dispersing agent,a soluble organic ester of an aliphatic monocarboxylic acid containing 2to 4 carbon atoms and an aliphatic alcohol containing 2 to 6 carbonatoms, said ester containing at least one solubilizing radical selectedfrom the group consisting of the sulfonate, sulfate, and phosphateradicals.

2. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding processes comprising, inaddition to a vat dye compound and a small amount of a dispersing agent,a soluble alkali metal salt of an organic ester of an aliphaticmonocarboxylic acid containing 2 to 4 carbon atoms and an aliphaticalcohol containing 2 to 6 carbon atoms, said ester containing in theacyl radical thereof at least one solubilizing radical selected from thegroup consisting of the sulfonate, sulfate, and phosphate radicals.

3. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding processes comprising, inaddition to an unreduced vat dye and a small amount of a dispersingagent, a soluble organic ester of an aliphatic monocarboxylic acidcontaining 2 to 4 carbon atoms and an aliphatic alcohol containing 2 to6 carbon atoms, said ester containing a sulfonate radical in the acylradical thereof.

4. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding processes comprising, inaddition to an unreduced vat dye and a small amount of a dispersingagent, an alkali metal salt of an ester of an aliphatic alcohol and analiphatic monocarboxylic acid containing 2 to 4 carbon atoms, thealcohol residue of said ester containing 2 to 6 carbon atoms, said estercontaining a sulfonate radical in the acyl radical thereof.

5. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding processes comprising, inaddition to a vat dye compound and a small amount of a dispersing agent,a soluble salt 01' an ester oi an aliphatic alcohol and sulfoaceticacid, the alcohol residue of said ester containing 2 to 6 carbon atoms.

6. A vat dye composition for use in the preparation ot printing pastesand padding baths comprising an unreduced vat dye, a dispersing agent,and an alkali metal salt an ester of an allphatic alcohol andsulfoacetic acid, the alcohol residue of said ester containing 2 to 6carbon atoms.

7. A vat dye paste for use in the preparation of printing pastes andpadding baths comprising an unreduced vat dye, a dispersing agent, andsodium isobutyl sulioacetate.

8. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding p comprising, in additionto a vat dye compound and a small amount oi a dispersing agent, aneutral soluble salt of isobutyl sulioacetate.

9. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding p comprising, in additionto an unreduced vat dye and a small amount oi a dispersing agent, analkali metal salt of isobutyl sulioacetate.

10. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding processes comprising, inaddition to a vat dye compound and a small amount of a dispersing agent,a neutral soluble salt of isobutyl sulfobutyrate.

11. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding processes comprising, inaddition to an unreduced vat dye and a small amount of a dispersingagent, an alkali metal salt of isobutyl sultobutyrate.

12. A vat dye paste for use in the preparation of printing pastes andpadding baths comprising an unreduced vat dye, a dispersing agent, andsodium isobutyl suliobutyrate. Y

13. A vat dye composition for use in connection with the coloring oitextile fibers by printing and pigment padding processes comprising, inaddition to a vat dye compound and a small amount of a dispersing agent,a neutral soluble salt of an ester of an aliphatic monocarboxylic acidcontaining 2 to 4 carbon atoms with an alcohol containing 6 carbonatoms.

14. A vat dye composition for use in connection with the coloring oftextile fibers by printing and pigment padding processes comprising. inaddition to an unreduced vat dye and a small amount of a dispersingagent, an alkali metal salt of cyclohexyl sulfoacetate.

15. A vat dye paste tor use in the preparation oi printing pastes andpadding baths comprising an unreduced vat dye, a dispersing agent, and

sodium cyclohexyl sulioacetate.

JEAN G. KERN.

